


Shadows

by happy_mystic



Category: Undertale (Video Game)
Genre: Dadster, Gen, LITERALLY, Skelefam, baby bones, gasterblaster!au, papa wolf gaster
Language: English
Status: Completed
Published: 2017-09-20
Updated: 2017-09-20
Packaged: 2019-01-01 03:33:51
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,106
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12147747
Author URL: https://archiveofourown.org/users/happy_mystic/pseuds/happy_mystic
Summary: There was one human that fell that never made it to Asgore.





	Shadows

**Author's Note:**

  * For [sushiinfood](https://archiveofourown.org/gifts?recipient=sushiinfood).



The trees and mountains were blurring, bouncing in Sans’s vision as they ran. He, too, along with Papyrus, bounced in Gaster’s grip.

As the three of them ducked into a cavern, Sans’s father finally slowed his pace. Amid the darkness, Gaster leaned against the rock wall, breathing deeply and clutching the two boys tightly against his ribcage.

“dad? that was a human, wasn’t it?” Sans hadn’t gotten a good look before Gaster had teleported the three of them and ran, but the creature pointing the sword at them was similar enough to the pictures in his history books from school. He could guess at it.

Gaster, still panting, said nothing. He followed the light of the glowing rocks overhead and set the two boys down next to a large rock. The cries of their attacker still rang out from afar, calling out for them.

“what’s going on?”

“Sans, listen to me,” Gaster said, bending down to face him. He was gripping Sans’s shoulders, almost tightly enough to hurt. “I need you and your brother to stay here and keep hidden. Keep very quiet, and whatever you might hear outside, _do not come out_ until I come and get you. Understand?”

Sans could feel Gaster’s hands shaking through his jacket. His eyes were wild in the light of the crystals. Sans could tell this was serious.

He nodded. “okay.”

Gaster briefly clicked his forehead to Sans’s. “Good boy.” Then he turned and was striding out towards the entrance.

Papyrus clung to Sans’s arm, reaching outwards to their father. “DADDY?”

“shh, pap.” Sans hugged him. Of course Papyrus wouldn’t know what was happening. He was only four.

Sans turned his gaze to the entrance of the cave. Gaster was no longer in sight.

He may have been just a kid, but Sans knew how powerful humans were.

Clenching his teeth, he began walking towards the entrance.

“SANS!” Papyrus called out to him from behind the rock.

“stay here, bro.”

Putting his fingertips to the rocky rim, Sans slowly peered out.

Gaster had turned a corner and gone out of sight, but there was a shadow cast against the walls of rock jutting above the path they had taken.

A figure shaped like their father was walking along the wall, slowly but with their head held high, before stopping in their tracks.

The figure suddenly seized up, trembling, doubling over and clutching at its head.

Pained gasping rang out, echoing down the stone corridor. Sans’s fingers tightened against the cave wall.

Its hands dropped onto all fours, bracing itself against the ground.

Spikes were growing out its back, as well as its arms and legs. Its mouth jutted out forward.

The rest of it, slowly, began to grow.

Its legs, its head, and its body stretched outward and upward. The sound of ripping fabric only slightly muffled the sound of crunching bone. Sans did his best to ignore a wave of nausea.

The gasps grew into a low, steady growl as the shadow finally stopped growing.

It was more canine-like now, on four legs, with a pointed snout and sharp fangs jutting out from it. A large tail, also spiked, flicked from behind it.

The beast lifted its head and let out a roar, loud enough to shake snow from the trees.

The sound of shouting began to gather in the distance and grew louder. A human shaped figure joined the beast’s shadow on the wall. It stopped dead in its tracks, staring upwards.

The creature didn’t let them stare long. It snapped its jaws at the human, growling again.

The human, quickly getting their nerve back, brandished their sword, swinging into a lunge.

The beast easily sidestepped it, opening its mouth in a roar. Putting weight on one foot, it leaned back, swiping the other one at the human, who was sent tumbling into the snow.

They struggled to their feet, settling into a fighting stance again.

The human swung their sword back and forth. The beast shifted, dodging the small creature in front of it.

Bending their legs, the human leapt forward, thrusting the sword out in front of them.

The beast misstepped, and the sword struck the beast’s front leg. Sans let out a small gasp.

The creature roared, rearing up into the air. The human took the opportunity to thrust their weapon forward, but aimed too low, and mercifully missed.

The beast snarled, dropping back down again. Leaning into the other three legs, it raised its tail, and with its entire weight, swung it at the human. They went flying backwards, smacking into a rock wall and sliding to the ground. They didn’t get back up.

The beast stepped forward heavily.

It opened its mouth a third time, wider than it had before.

Against the beasts’s shadow, a blue light began to glow where its eye would be, and another one inside its mouth. It kept growing bigger and bigger until it shot forward, filling the entire cavern with light, along with a loud blast. Sans covered his eyes.

A softer sound, one that sounded like something shattering, followed.

When Sans uncovered his eyes, there was only one shadow remaining.

For a moment, the only sound was the beast’s heavy breathing. Sans tried to stop himself from shaking.

Then the shadow began to shrink, the spikes, snout, teeth and tail disappearing - until it was back to its original form, lying on all fours on the ground.

The figure lay like that for a good moment, before it got to its feet.

It flicked something off its hands with a huff.

“Humans. So messy.”

It looked around, taking stock of its surroundings.

“Sorry, Asgore,” Sans heard his father’s voice mutter. “There’s one soul you won’t be getting your hands on.”

The figure slowly made its way towards the cave, hunched over and limping slightly, arms at its side.

Quickly, Sans ran back into the cave to his brother, who was still behind the rock. Sans put his arms around him.

Gaster finally walked into view. He was covered in something red and wet looking. It dripped from his torn-up coat as he walked.

“DADDY!” Papyrus ran towards him. Sans followed after.

Gaster stood there, his mouth tight. His sons stared, not knowing what else to do.

He fell, rather than knelt, down next to the boys. He wrapped his arms around them, pulling them in close.

The three of them stayed that way for a very long time.

\-----

When they were finally able to talk about it, Sans said that it had been the scariest day of his life.

Gaster had nodded.

“It was mine, too.”


End file.
